Sewing machine



1931. A. J. WOHLPART 3 SEWING MACHINE Filed June 19, 1926 2 Sheets-Sheet1 INVENTOR ATTORNEY Feb. 17, .1931. A, J, WOHLPART 1,792,722

SEWING MACHINE Filed June 19, 1926 2 Sheets-Sheet 2 lNVENTOR ATTORNEYPatented Feb. I 17, 1931 UNITED-STATES PAT AUGUST JOHN WOHLPART, or NEWYORK, N.IY.. ASSIGNOR T L. BULASKY, rNooR- IPORA'IEID, or NEW YQRK, N.Y.

V snwI G MACHINE imitatio filed June 19,

This invention relates to improvements in sewing,machinesand has for oneof its objects to eflect, by a novel combination of parts,

a readily adjustable device for producing stitching from various rangesor widths of zigzags, to simple straight stitching.

With the present construction, my machine may sew stitches'continuouslyin a straight line or ordinary sewing, or it may produce 10 zigzagstitches of different width of throw up to, three eighths ofaninch, ormore, if

necessary. a I

With the above objects, and certain other objects also 'in view whichwill become apparent as the present description proceeds, my inventionconsists in the novel parts, and combinations of parts, all; ashereinafter will be more fully described and particularly pointed out inthe claims. 4 29 Referring to the accompanying drawings forming a partof this specification in which like numerals designate like parts in allthe views: r

Figure I is a side view ofa small sewing 'machine embodying myattachment for zigzag stitches of various width.

Figure II is the end view of this machine looking at it from the needle,feed mechanism, and stitching end. 7 I 1 Figure III is a detail Viewlooking down upon the mechanism specific to the zigzag drivingmechanism. f 1

With further reference to Figure -I,'10 is a stationary frame casting ofusual sewing machine design integral with bed plate 11 adapted tosupport and guide, as well'as-to provide pivots, bearings, etc, etc.for' the working parts of the machine. The bed plate 11 is adapted tomounting upon a table or other suitable support. I

The main shaft 12 of the machine is mounted in suitable bearings in theframe, and isprovided as usual, with a driving pulley or belt wheel 13,shown broken away, and an eccentric 14 which through the-apltman 15,lever 18, pivoted at 17, shown broken away, and the link-member 19,imparts to the needle bar its vertical reciprocations. r

The needle bar 20 is arranged to carry the 1926. Serial No. 117,070.

ENT OFFICE the casting 10 as indicated bythe positions of the slot-way23' which is cut in the frame casting 22. A screw 24 enters into andengages threads in the stationary frame 10, and the oscillating motionis produced by the lever 25 adjustably and yieldingly connected to theframe 22 by the screw pivot 26 working in a slot provided therefor insaid frame. The lever 25 is hinged, or pivoted, at 27 to a long ribbedlever 28, and which is again 'lever 28 moves to the left andconsequently also moves the pivot 27 to the left, and this in turn movesthe lever 25 to the left, which in turn moves the frame22 to theleft,and since the frame 22'is pivoted to the casting 10, it swings the pointof the needle 21 to the right. The lower end of the lever 28 hasassociated therewith the adjustably slotted stud 36, shown in dottedlines, for drivingly connecting the link 48, also shown in dotted lines,with said lever, and said link is adjustably secured by the stud 52 inthe frame or yoke 40. This frame or yoke 40 is in turn driven to theright and to the left,.alternately, bythe stud 39 of the link 37 and thestud 38 in the radial slot-way 50, of the complex quadrant lever 49,which along with the lever 28 is also pivoted and free to swing aboutthe common large stud 29. This complex quadrant lever 49 hasa rollerP111011 its reverse side, shown in dotted lines at 30, and the saidroller pin 30 imparts a right and left, back and forth swingingmovementto the complexquadrant lever 49, as the roller pin is it selfdriven back and forth, right and left, in its engagement with the camslot of the roller 32. The roller 32 is driven by the large gear 33which it engages, and the large gear 33 is in turn driven by the smallergear 35 and the main shaft 12. The complex quadrant lever 49 withitscurved radial slotway 50 is calibrated off into the divisions 51.

hen the link 37 is in the position shown inthe drawing, with thestud orwrist pin 38 at the extreme upper end of the radial slotway 50, there isno back and forth motion imparted to the link 37, when the complexradial lever 49 moves about thepivot29 as maybe seen, andconsequentlythere is no motion imparted to the frame or yoke l0,becauseof the close proXimity'of-the studor'wrist pin 38 to thelargepivot stud 29. The minimum motion of the quadrant slotway'is,therefore,

at its upperend, and the maa rimumqn'otion of the-said quadrant slotway1S2Li-tl1 lower end, and the intermediary motions are indicated by thecalibrateddivisions 51, already referred to, To more easily changetheposition P of the --li nk; 37, the stud 38 may conveniently'beprovided with aknnrled head or wings for-ready adjustment as desiredwhile the machine 1s1noperat1on,as will heapparent.

Theframeor yoke 40, isattachedat its lefth'ano end-tothe bar 41 which isadapted'to slide back and forth through therguide bearings 42 and 4a.

The bar hasattached fast to itpthe member tand"throughthe extensionfinger 44' runningin-a slotinthe member 45 it slides the said member45to the right and to-the left on themainshaft 12, when driven bythecordance with previous patent disclosuresin this art, and, therefore,itisnotdeemed essential to illustrate-it in moredetail here.

V VVith further reference to Figure II, 20'is the reciprocating needlebar, 18 the end of the driving lever, 19 the connecting link betweenlever and needle bar 20, 22the oscillating frame guiding the needlebar20, 10 the stationary frame of themachine, 5'5the-pivot between themoving frame 22:and the stationary frame casting 10. 29 is the largecommon stud for the lever 28 and thecomplex quadrantlever 49.38-istheentl of the stud whichslides down throughthe slotof the complexquadrant lever 49. 37 is theconnecting link-and 39 the lowerstudadaptedto drive the-frame or yoke 40. 48' showsthe end of the driving linkconnected to the lower end 28 of the lever 28. 11 shows the bed plate,12 is the main shaft of the machine, and 47 is the looper on the saidmain shaft- 12 together with the small gear 35 which meshes with anddrivesthe large'gear 33 on the cam 32 which engages-theroller stud 30.

With further reference to Figure III these same numbers and parts areshown looking =down "from above -'the respective parts -m-ay beidentified by like numbers.

From an inspection and analysis of these mechanisms it may now beappreciated that by the single movement of the stud 38 along the radialand calibrated slot-way 50 of the cnmplex quadrant lever 49, Isimultaneously effect adjustment of both'sewingneedle and looper.

It will also'be appreciated from an inspection and analysis of thesemechanisms that r the machinewill sew straight or conventional stitcheswhen the mechanism is set in theposition shown, and furthermore, whilethemachine-is in operation it'is possible to make the change fromstraight or conventional stitchingto zigzag stitchlng.

Whereas I have shown one design of a mechanism for simultaneouslycontrolling the lateral oscillations of needle bar and looperrespectivelygI wish it to be understood that I do not confine myself tonarrow or specific details, but ratherto the broad invention ofsimultaneous needleb'ar and looper control and adjustmentthrough theagency of a conveniently moved and simple lever, or its-equivalent.

Having described my invention 1 claim 1. A sewing machine adapted tomakezigfzaig stitches, comprising a'needle bar,a'lever for oscillatingthe same, a looper, single means commonly pivoted with saidlever forcontrolling the increase or decrease in the lateral movements of'thesaid needle bar and looper, and driving connections between said meanssaid lever and said looper.

2. A sewingmachine adaptedto make zigzag stltches, comprising asynchronized needlebar and looper, a'lever for oscillating the former,means commonlypivoted with sait lever for simultaneouslycontrolling theincrease or decrease in'the lateral oscillatory movement of the saidneedle bar andlooper,

-a*m.ain driving shaft, and driving connections between said shaft saidlever and said looper.

3. A sewing machine adapted'tomake zigzagstitchescomprising a needlebar, a lever for oscillating'thesame, a looper, andm'eans commonly:pivoted with 'said lever for predeterminedly and graduatingly'controlling the lengths of the zig-zag stitches.

4.1L sewing machine adapted to make zigzag'stitches, comprising a needlebar and a looper, a needle bar reciprocating lever, a

-needle -baroscillating lever, a: reciprocating needle bar oscillatinglever, and the said r eciprocating looper shaft respectively.

5. A sewing machine adapted to make straight conventional stitches, orzig-zag stitches of varying lengths at will, comprising a needle bar, alooper, a needle bar reciprocating lever, a needle bar oscillatinglever, a reciprocating looper shaft, and a reciprocating looper shaftmechanism, a main shaft, a gear on said main shaft, a jack shaft, a gearon the said jackshaftengaging the gear on the main shaft, a cam with aneccentric slot-way on the jack shaft gear, a roller pin in the saideccentric slot-way and fixed to a lever commonly pivoted with saidoscillating lever and provided with a radial slotway and a movable andadjustable link, and driving connections between said link and saidoscillating lever, said link adapted to drive simultaneously the saidneedle bar oscillating lever, and the said reciprocating looper shaftmechanism.

6. A sewing machine adapted to make zigzag stitches of various lengths,comprising a needle bar and associated leverfor oscillating the same, amain drive shaft, a looper, and driving connections between said shaftsaid looper and said lever including means commonly pivoted with saidlever for controlling the length of stitch desired.

7 A sewing machine adapted to make zigzag stitches of various lengths,comprising a needle bar and associated lever for oscillating the same, amain drive shaft, a looper, and driving connections between said shaftsaid looper and said lever including singly operated means comprising asecond lever commonly pivoted with said first named lever and a linkadjustably associated with said second lever, said means adapted topredeterminedly and variably control the movements of said needle barand said looper.

8. A sewing machine adapted to make zigzag stitches of various lengths,comprising a synchronized needle bar and looper, a link for oscillatingthe needle bar, a lever for actuating said link, means commonly mountedwith said lever for simultaneously controlling the increase or decreasein the degree of lateral oscillation of the said needle bar and looperrespectively, and driving connections between said means, said lever andsaid looper.

Signed at New York city in the county of New York and State of New York,this 16th day of June, A. D. 1926. 7

AUGUST JOHN WOHLPART.

